An electron beam detector is for detecting a secondary electron emitted from a sample surface by an electron beam with which the sample surface is irradiated from an electron gun. For example, the electron beam detector is used as a secondary electron detector (SED) constituting a scanning type electron microscope (SEM) or the like. With use of a SEM, it is possible to recognize a surface state of a sample in the form of an image.
The secondary electron detector comprises: a scintillator that emits light by converting an incident secondary electron into visible light, ultraviolet light or the like; and a photoelectron multiplier tube that converts light emitted from the scintillator into electric energy.
Until now, a single crystal YAG is known as a material of the scintillator as described in the paragraph [0031] of Patent Document 1 (Japanese Patent Laid-Open No. 2001-243904). Further, Patent Document 2 (Japanese Patent Laid-Open No. 2009-99468) describes a phosphor layer formed by coating a mixture of phosphor powder such as ZnO with an adhesive on a transparent substrate or the like and then drying it.